1. Field of the Invention
The present invention is related to a light emitting module.
2. Description of the Related Art
Japanese Patent Application Publication No. JP-A-08-130320 discloses a light emitting module comprising a package, a heat sink, a sub-mount, and a semiconductor laser diode (will be referred to as “LD” hereinafter) The package includes a stem and a cap, and the heat sink is mounted on the stem. The heat sink has a mounting surface extending along an optical axis direction, and the LD is mounted on the mounting surface via the sub-mount.
In the light emitting module, the LD is fixed to the sub-mount, and the sub-mount is fixed to the mounting plane with solder. That is, the LD is first mounted on the sub-mount, and, the sub-mount on which the LD has been mounted is thereafter mounted on the heat sink. However, the latter soldering may affect the former solder, which may cause a shift of the optical axis of the LD.